Fish Surveys

Published

May 4, 2024

Metadata

Figure 1: Location of fish surveys
Table 1: Summary of work by island and exposure
Number of fish surveys per location, habitat, and exposure
Exposure Strata # Sites # Transects # Reels Surveyed distance (m)
Fanna
Forereef Leeward 2 1 2 6 150
Forereef Windward 2 5 10 30 750
Total — — 6 12 36 900
Helen
Backreef Lagoon 1 1 2 6 150
Patchreef Lagoon 2 3 6 18 450
Forereef Leeward 2 6 12 36 900
Forereef Windward 2 5 10 30 750
Total — — 15 30 90 2250
Merir
Forereef Leeward 2 3 6 18 450
Forereef Windward 2 4 8 24 600
Total — — 7 14 42 1050
Pulo Anna
Forereef Leeward 2 2 4 12 300
Forereef Windward 2 2 4 12 300
Total — — 4 8 24 600
Sonsorol
Forereef Leeward 2 4 8 24 600
Forereef Windward 2 3 6 18 450
Total — — 7 14 42 1050
Tobi
Forereef Leeward 2 5 10 30 750
Forereef Windward 2 1 2 6 150
Total — — 6 12 36 900
Grand total — — 45 90 270 6750

QA/QC

Taxa

Observations

Location summary

Table 2: Summary of results by island and depth strata.
Average species richness, abundance, and biomass by location
Sites # Transects # Reels # Taxa Abundance (ind/m2) Biomass (g/m2)
Fanna
Deep 6 6 18 77.50 13.76 751.83
Shallow 6 6 18 60.83 14.36 328.81
Overall — 12 36 69 14 540
Helen
Deep 14 15 45 67.80 6.82 696.49
Shallow 14 15 45 74.87 9.73 646.62
Overall — 30 90 71 8 672
Merir
Deep 7 7 21 67.57 6.33 875.68
Shallow 7 7 21 73.43 5.68 697.21
Overall — 14 42 70 6 786
Pulo Anna
Deep 4 4 12 61.25 17.72 1431.37
Shallow 4 4 12 67.50 10.43 756.46
Overall — 8 24 64 14 1094
Sonsorol
Deep 7 7 21 72.57 17.38 552.88
Shallow 7 7 21 64.00 17.22 422.41
Overall — 14 42 68 17 488
Tobi
Deep 6 6 18 69.50 7.87 879.63
Shallow 6 6 18 73.17 13.96 676.63
Overall — 12 36 71 11 778

Analyses

Diversity

Figure 2: Number of species by order and family
Figure 3: Species richnnes by island
Table 3: Results of Adonis model for univariate analysis of fish species richness
Results of Adonis model for univariate analysis of fish species richness
df SumOfSqs R2 statistic p.value
depth_strata 1 17.187 0.001 0.134 0.721
location 5 700.063 0.061 1.095 0.391
exposure 1 865.000 0.075 6.763 0.018
habitat 1 17.074 0.001 0.133 0.701
diver 1 18.771 0.002 0.147 0.700
Residual 79 10104.930 0.877 NA NA
Total 89 11527.156 1.000 NA NA
Figure 4: Species richnnes by exposure by island

Abundance

Figure 5: Fish abundance by island
Table 4: Results of Adonis model for univariate analysis of fish abundance
Results of Adonis model for univariate analysis of fish abundance
df SumOfSqs R2 statistic p.value
depth_strata 1 29.318 0.006 0.767 0.399
location 5 1245.230 0.235 6.515 0.001
exposure 1 229.449 0.043 6.003 0.017
habitat 1 2.019 0.000 0.053 0.797
diver 1 695.530 0.132 18.196 0.001
Residual 79 3019.706 0.571 NA NA
Total 89 5289.048 1.000 NA NA
Figure 6: Abundance by exposure by diver
Figure 7: Abundance by exposure by island

Biomass

Figure 8: Fish biomass (g/m2) by island
Table 5: Results of Adonis model for univariate analysis of fish biomass
Results of Adonis model for univariate analysis of fish biomass
df SumOfSqs R2 statistic p.value
diver 1 281913.07 0.015 2.014 0.161
depth_strata 1 965942.72 0.051 6.899 0.009
habitat 1 16539.82 0.001 0.118 0.716
exposure 1 1580881.99 0.084 11.291 0.001
location 5 3247391.55 0.173 4.639 0.001
Residual 79 11060545.73 0.588 NA NA
Total 89 18812734.31 1.000 NA NA

By depth

Figure 9: Biomass by depth strata by island

By exposure

Figure 10: Biomass by exposure by island
Table 6: Summary of results by island and exposure
Average species richness, abundance, and biomass by location and exposure
Sites # Transects # Reels # Taxa Abundance (ind/m2) Biomass (g/m2)
Fanna
Leeward 1 2 6 69.50 10.40 812.14
Windward 5 10 30 69.10 14.79 485.95
Helen
Lagoon 4 8 24 67.88 8.04 191.03
Leeward 6 12 36 66.42 6.01 544.84
Windward 5 10 30 80.00 11.18 1208.03
Merir
Leeward 3 6 18 68.17 5.40 867.84
Windward 4 8 24 72.25 6.46 725.40
Pulo Anna
Leeward 2 4 12 62.00 13.51 667.86
Windward 2 4 12 66.75 14.64 1519.97
Sonsorol
Leeward 4 8 24 65.50 13.97 399.07
Windward 3 6 18 72.00 21.74 605.73
Tobi
Leeward 5 10 30 70.90 11.36 749.79
Windward 1 2 6 73.50 8.67 919.82

By family

Figure 11: Biomass by family
Figure 12: Biomass by family and depth strata

By trophic group

Figure 13: Biomass by trophic group

By species

Figure 14: Frequency, abundance, and biomass by species

Community assemblages

Table 7: Fish assemblages Adonis model
Figure 15: Principal coordinates analysis
Table 8: Results of ANOVA on the ordination model